1. Field of the Invention
The present invention relates to a clasp used in a clasp or hook for an annular accessory such as necklace, to fastens and unclasps a string, chain, or the like, or used in a pendant or key holder with decorative portion to connects the main portions thereof, and a process for producing the same.
2. Description of Related Arts
In conventional, a clasp for necklace has been known as a faster and its production in Japanese Utility Model No. 57-88407.
Referring to FIG. 12A, which shows the conventional clasp, where FIG. 12A is a plane view, FIG. 12B is a cross-sectional view of the line A—A, and FIG. 12C is a cross-sectional view of the line B—B, a clasp 600 comprises a pair of members consisting of a male member 61 capable of being inserted into a female member 62, a communicating projection 65 (hereinafter referred to as “hereinafter referred to as “lock pin”) composed of an elastomer vertically provided on the male member 61 in the direction perpendicular to the advance and retreat direction thereof, and upon locking the faster, the lock pin 65 is inserted into a concave portion 74 provided on the female member 62 and it is revolved.
Upon releasing the locked state, when the male member 61 is revolved relative to the female member 62, the lock pin 65 fellows a separating route 72 to be separated from the concave portion 74, whereby the male member 61 can be separated from the female member 62. In addition, in order to avoid unwanted, unexpected releasing of the lock, the lock pin 65 is communicated with the concave portion 72 so that the lock pin does not come out from the separating route 72 in a spontaneous manner. Specifically, the lock pin 65 cannot be separated from the concave portion 74 unless a user spins the male member 61 relative to the female member 62, while putting up the elastic force.
However, releasing the lock in the clasp 600 constructed as described above, the male member 61 must be spun relative to the female member 62 so that the lock pin 65 may follow the separating route 72 to be separated from the concave portion 74. Evan if the amount of the spinning is approximately 45°, there is a disadvantage in terms of difficult operation. Especially, in the case where the clasp is small, it is very difficult to conduct the spinning operation. Also, for the user, when the clasp is unclasped around the neck, which is difficult to be viewed, it is very difficult to conduct adequate spinning.
It is, therefore, the object of the present invention is to provide a clasp, which is difficult to be separated when the user does wants to be separated, which can easily be separated, when the user wants to be separated, and which has a simple structure so that there is no limitation in terms of design; and to provide a process for producing such a clasp in an easy manner.